Surf towboard



Sept. 30, 1969 D. L. COLE SURF TOWBOARD Filed Sept. 5, 1968 INVENTOR. flauz'a'l. Gale United States Patent 3,469,554- SURF TOWBOARD David L. Cole, San Jose, Calif. (P.O. Box 487, Waterford, Calif. 95386) Filed Sept. 5, 1968, Ser. No. 757,743 Int. Cl. B63h 19/04 US. Cl. 115-4 6 Claims ABSTRACT OF THE DISCLOSURE An apparatus utilizing offshore currents for propelling a device attached thereto seaward, A semi-buoyant device which when cast into the incoming waves of a surf utilizes the offshore under currents for propelling the device seaward.

BACKGROUND BRIEF SUMMARY OF INVENTION The present invention relates to a semi-buoyant towboard constructed to utilize sub-surface currents to propel the device in an offshore direction. The device is primarily an amusement device for use a lakeshore or seashore where waves come in and break in foaming billows upon the beach commonly known as surf. The device is connected to a line under the control of a person standing on the beach much the same as a kite is flown in the air on the end of a length of string. Accordingly the device of the present invention may be referred to as a Surf =Kite.

In this connection itwill be appreciated that as the power of each wave dissipates on the beach its recession seaward builds up a concomitant powerful flow. It is within this seaward current associated with the undertow that the device of the present invention is propelled.

It is an object of this invention to provide a semibuoyant framework supporting a panel on which a fin or fiap is hingedly mounted such as to be effected by the force of the flow of current in the back wash or undertow of the surf.

It is another object to provide a device constructed to present an upstanding flap vane on its upper surface so mounted -as to obtain a one-way propulsion in an offshore direction.

It is a further object to provide a line towing device influenced by oifshort currents in a surf for pulling the device and line seaward.

These and other objects and advantages of the present invention will become apparent from a reading of the following description in the light of the drawing in which:

FIG. 1 is an illustration of a surf in which the device of the present invention is shown in use;

FIG. 2 is a top side perspective view of the device of the present invention;

FIG. 3 is a view similar to that of FIG. 2 but a larger scale illustrating structure;

FIG. 4 is a longitudinal section, fore to aft of FIG. 3 taken along line 44 therein;

FIG. 5 is a bottom side perspective view of the device of FIGS. 2 and 3.

In the drawing the device, generally designated 10 comprises a framework 11 of tubular members 12 having their ends 13 collapsed and sealed to provide air cham bers 14 in each member. In the present disclosure the frame 11 is of triangular form but it should be understood that various forms and shapes may be employed.

Each tubular member 12 is secured to an adjacent contiguous member by a rivet 15 or any other suitable means to form a corner angle between the various sides of the frame 11. For purposes of orientation one tubular member 12' is considered the aft or stem end of the device 10 and the apex A formed at the opposite angle of the other two sides is considered the fore or how end of the device.

A platform 16 is mounted on the top of the frame 11 by means of bolts 17 which extend down through the side tubular members below. This platform 16 is shaped comparable to the frame 11 but foreshortened at the fore end 18. In the present illustration the platform 16 is of a frustrated triangular shape leaving an open zone 0 adjacent the fore end of the frame between the fore end 18 of the platform and the apex A of the frame.

A flap vane 20 is pivotally mounted as at 21 on the top surface 22 of the platform 16 adjacent the fore end 18 of the latter. The pivotal mounting 21 is a hinge 23 having one wing 24 thereof secured to a mounting plate 25 which in turn is secured to the platform 16 by suitable bolts 26. The other wing 27 of hinge 23 is secured to the vane 20 in such a manner as to normally support the vane at a slight angle (FIG. 4) relative to the top surface 22 of the platform. The flap vane 20 is of a length to extend its edges 28 and 29 to parallel relation adjacent the side edges 30 and 31, respectively, of the platform 16.

The hinge arangement 23 is also constructed to limit swinging movement of the vane 20 beyond a substantially normal perpendicular disposition relative to the top surface 22 of the plat-form. This is accomplished by abutting knobs 33-34 on the respective hinge wings 24 and 27.

Means for maintaining the device 10 on the fore to aft course consists of a keel 35 in the form of one or more fins which extend downwardly from the underside 36 of the platform 16. In FIG. 5 a pair of such fins is shown, one 37 and the other 37' of identical construction. It should here be noted that the fins 37-37 may be an integral part of the platform 16 as may the mounting plate 25 for the front wing of the hinge 23. These units may be cast in plastics or otherwise molded into an integral member.

The keel fins 37 and 37' being identical like parts are designated by like reference numerals. Suffice it to say that they are equally spaced from longitudinal, fore to aft, center of the device so as to balance the same in buoyancy and direction of movement. Each fin 37 and 37 is a thin Wedge shaped member having its greatest depth at the aft end, In the present disclosure each wedge shaped fin 37 and 37' is secured to a mounting member 38-38, respectively, each of which is secured to the platform by suitable bolts 39.

In use a yoke-like leader L has the free end of each strand thereof tied to the respective base angles at the stern end of the frame 11 as illustrated in FIG. 2. From this yoke L a single strand of cord C such as a fishline or other suitable cable extends from a reel or ball thereof as shown in FIG. 1. The device 10 is cast into the surf, top surface up so that the flap vane 20 assumes a position to be influenced by the current of the water. The device 10 having air chambers 14 in each of its side members 12 balanced against the mass or weight of the platform and accouterments is semi-buoyant and therefore levels below surface of the water. At seaside the specific gravity of the salt water is such that the device 10 levels in the undercurrent stream as indicated by the arrowsa-in FIG. 1. Thus the force of the water flips the flap vane 20 into its vertical position (FIGS. 1 and 4) whereby the entire device is propelled offshore with the out-going undertow current. The person manning the line or cord C allows the latter to pay out as far as desired or as the length of line will permit.

The cord may be on a reel such as is used in fishing gear thus keeping the line C from becoming tangled. Otherwise the cord may be wound in a ball or on 'a stick in the manner of flying a kite.

To release the device for easy return the person manning the line C merely pulls back upon the line in a jerking fashion such that the current of the water causes the device to flip over. In other words, a shoreward jerk on the line and sudden release will raise the device to the incoming wave stream whereby it pivots shoreward about an axis defined by the base end 12' of the triangular frame 11. Thus the device is inverted to overlie the yoke L and the vane 18 will be suspended downwardly whereby the flap vane 18 now serves as an elevator vane effected by the shoreward pull on the line C to keep the semibuoyant device up in the strata of the incoming waves.

While the device 10 is primarily intended as an amusement device it also has practical uses such as a tow plate for carrying fishing hooks on lines out into the surf and more calmer water.

It is also conceivable that the device 10 employed on a surfboard can be used to assist the surfer in getting out beyound the swells before mounting the surfboard for a shoreward ride.

While I have described the device of this application in specific detail it will be appreciated that the same may be susceptible to variations, alterations and/or modifications without departing from the spirit of my invention therein. I therefore desire to avail myself of all variations, alterations and/ or modifications as may fairly come within the purview of the appended claims.

What I claim as new and desire to protect by Letters Patent is:

1. A surf towboard having a bow and stem end and comprising (a) a framework of hollow semi-buoyant members providing sealed chambers;

(b) a platform secured to said framework; and

(c) propulsion means therefore comprising a vane mounted on and adjacent the bow end of said platform for pivotal movement between said platform and a substantially vertical disposition relative thereto dependent upon the force of the current of the surf for propelling said tow-board seaward.

2. The device in accordance with claim 1 in which said framework has a tow line secured to its stem end.

3. The device in accordance with claim 2 in which said framework is triangular in shape having its apex forming the bow end and its aft side opposite the apex thereof forming the stem end of said towboard.

4. The device in accordance with claim 3 in which said platform is a frustum of a triangle conforming in shape to said framework to provide an open zone between the fore end of said platform and the apex, bow end of said framework.

5. The device in accordance with claim 4 in which said propulsion means comprises -(a) a fixed hinge wing secured to said platform adjacent the fore end thereof;

(b) a movable hinge wing pivotally connected to the fixed hinge wing;

(c) a vane secured to said movable hinge wing and having end edges parallel to the adjacent side edges of said platform; and

(d) means for limiting movement of said vane beyond a slight angular disposition relative to said platform, and means for limiting movement of said vane beyond substantially perpendicular relation relative to said platform.

6. The device in accordance with any one of claims 1, 2, 3, 4 and 5 including a keel fin extending downwardly from the lower surface of said platform for maintaining said towboard in fore to aft alignment with the direction of fiow of a current applied to said vane.

References Cited UNITED STATES PATENTS 1,315,267 9/1919 White 4 2,509,323 5/1950 Underhill 1l5-4 XR ANDREW H. FARRELL, Primary Examiner 

